Dramatic umbrella cloud rising to an estimated10,000 m (33,000 ft) above sea level over Sheveluch Volcano on the Kamchatka Peninsula during the explosive dome collapse event of March 29, 2007. According to observers, a pyroclastic flow accompanied the formation of this eruption column and cloud. Photograph taken in the nearby community of Klyuchi by Yuri Demyanchuk, Director of the Levinson-Lessing Kamchatkan Volcanological Station at Klyuchi (Institute of Volcanology and Seismology) and Engineer for the Kamchatkan Branch of Geophysical Surveys. Used with permission.